I have been monitering the temperature in my 2g Eclipse Explorer tank with the Bio Wheel filter and have found that the filter motor produces enough heat to keep the water 82 degrees inside a house that is kept at 74 at night and 78 during the day so I find that no heater is necessary. I am planning on using it as a hospital or quarantine tank later on.

If the motor is heating it up that much... that isn't good. That'll cause HUGE fluctuations. Say... your house gets to 85 or 90. that's 8 degrees to 4 degrees difference for your tank and your house right now... 82 becomes 93, and 94. Plus take in mind more bodies in the house = more heat for the house, less bodies = cooler house, plus sunlight, breezes, baths/showers, etc.